Items such as pillows, comforters, ski jackets, ski vests, and the like are conventionally filled with an insulating material such as down, fiber fill, or the like, and it is desirable that these insulating materials be retained within the items and do not penetrate the fabric covering material during normal use. To this end, the fabrics used in such items are typically of a closely woven construction, and are often subjected to fabric finishing treatments (often called "down proof" finishes) to reduce the size of the interstices between the yarns and thereby prevent the penetration of the down or other insulating materials.
Down proof finishes have traditionally depended upon calendering fabrics that have been finished with conventional durable-press resin formulations, such as an n-methylol resin, catalyst, wetting agent, and softener. It is also known that starch will act as a filling agent when added to the above-noted type of durable-press finishing formulation, and will reduce fabric permeability to a limited degree. Starch, however, will promote a harsh fabric handle and causes dusting problems in production, in subsequent cut and sew operations, and in use.